#!/bin/sh
# Copyright © 2007       Kees Cook <kees@outflux.net>
# Copyright © 2007-2009  Roger Leigh <rleigh@codelibre.net>
#
# schroot is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# schroot is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see
# <http://www.gnu.org/licenses/>.
#
#####################################################################

set -e

. "$SETUP_DATA_DIR/common-data"
. "$SETUP_DATA_DIR/common-functions"
. "$SETUP_DATA_DIR/common-config"

# Wrapper around kill command. Turns errors into
# warnings when running in verbose mode, otherwise
# it ignores them.
# args: parameters for kill
kill_proc()
{
    if ! kill "$@" 2>/dev/null; then
        info "kill $@ failed: process already terminated?"
    fi
}

# Kill all processes that were run from within the chroot environment
# $1: mount base location
do_kill_all()
{
    chroot_path=$(realpath "$1")
    if [ -z "$1" ]; then
        fatal "No path for finding stray processes: not reaping processes in chroot"
    fi

    info "Killing processes run inside $1"
    ls /proc | egrep '^[[:digit:]]+$' |
    while read pid; do
        # Check if process root are the same device/inode as chroot
        # root (for efficiency)
        if [ /proc/"$pid"/root -ef "$chroot_path" ]; then
            # Check if process and chroot root are the same (may be
            # different even if device/inode match).
            root=$(readlink --canonicalize /proc/"$pid"/root || true)
            if [ "$root" = "$chroot_path" ]; then
                exe=$(readlink /proc/"$pid"/exe || true)
                info "Killing left-over pid $pid (${exe##$1})"
                info "  Sending SIGTERM to pid $pid"

                kill_proc -TERM "$pid"

                count=0
                max=5
                while [ -d /proc/"$pid" ]; do
                    count=$(( $count + 1 ))
                    info "  Waiting for pid $pid to shut down... ($count/$max)"
                    sleep 1
                # Wait for $max seconds for process to die before -9'ing it
                    if [ "$count" -eq "$max" ]; then
                        info "  Sending SIGKILL to pid $pid"
                        kill_proc -KILL "$pid"
                        sleep 1
                        break
                    fi
                done
            fi
        fi
    done
}

if [ $STAGE = "setup-recover" ] || [ $STAGE = "setup-stop" ]; then
    do_kill_all "$CHROOT_PATH"
fi
